English
Related papers

Related papers: Thermoacoustic tomography for an integro-different…

200 papers

In this work, it is shown that image reconstruction methods from ultrasonic imaging can be employed for thermographic signals. Before using these imaging methods, a virtual signal is calculated by applying a local transformation to the…

Data Analysis, Statistics and Probability · Physics 2017-03-16 Peter Burgholzer , Michael Thor , Jürgen Gruber , Günther Mayr

Ultrasound attenuation is caused by absorption and scattering in tissue and is thus a function of tissue composition, hence its imaging offers great potential for screening and differential diagnosis. In this paper we propose a novel method…

Signal Processing · Electrical Eng. & Systems 2019-10-15 Richard Rau , Ozan Unal , Dieter Schweizer , Valery Vishnevskiy , Orcun Goksel

This article addresses the inverse problem of simultaneously recovering both the wave speed coefficient and an unknown initial condition (acting as the source) for the multidimensional wave equation from a single passive boundary…

Analysis of PDEs · Mathematics 2025-07-29 Yavar Kian , Hongyu Liu

We consider the ultrasound imaging problem governed by a nonlinear wave equation of Westervelt type with variable wave speed. We show that the coefficient of nonlinearity can be recovered uniquely from knowledge of the Dirichlet-to-Neumann…

Analysis of PDEs · Mathematics 2022-02-04 Sebastian Acosta , Gunther Uhlmann , Jian Zhai

An instantaneous time mirror (ITM) is an interesting approach to manipulate wave propagation from the time boundaries. In the time domain, the reversed wave is previously proven to be the temporal derivative of the original pattern. Here,…

Classical Physics · Physics 2020-08-19 Danming Peng , Yiyang Fan , Ruochen Liu , Xiasheng Guo , Sihui Wang

We consider the inverse problem of determining the initial states or the source term of a hyperbolic equation damped by some non-local time-fractional derivative. This framework is relevant to medical imaging such as thermoacoustic or…

Analysis of PDEs · Mathematics 2021-11-10 Xinchi Huang , Yavar Kian , Eric Soccorsi , Masahiro Yamamoto

Photoacoustic computed tomography (PACT) is an emerging computed imaging modality that exploits optical contrast and ultrasonic detection principles to form images of the absorbed optical energy density within tissue. If the object…

Medical Physics · Physics 2017-09-08 Joemini Poudel , Thomas P. Matthews , Lei Li , Mark A. Anastasio , Lihong V. Wang

Photoacoustic tomography (PAT) is a novel and rapidly promising technique in the field of medical imaging, based on the generation of acoustic waves inside an object of interest by stimulating non-ionizing laser pulses. This acoustic wave…

Analysis of PDEs · Mathematics 2022-02-08 Hyungyeong Jung , Sunghwan Moon

This work studies the inverse problem of photoacoustic tomography (more precisely, the acoustic subproblem) as the identification of a space-dependent source parameter. The model consists of a wave equation involving a time-fractional…

Numerical Analysis · Mathematics 2025-04-29 Phuoc-Truong Huynh , Barbara Kaltenbacher

In this paper we consider the problem of acoustic inversion in the context of the optoacoustic tomography image reconstruction problem. By leveraging the ability of the recently proposed diffusion models for image generative tasks among…

Image and Video Processing · Electrical Eng. & Systems 2024-04-17 M. G. González , M. Vera , A. Dreszman , L. J. Rey Vega

Photoacoustic tomography is a hybrid biomedical technology, which combines the advantages of acoustic and optical imaging. However, for the conventional image reconstruction method, the image quality is affected obviously by artifacts under…

Image and Video Processing · Electrical Eng. & Systems 2024-06-26 Bowei Yao , Yi Zeng , Haizhao Dai , Qing Wu , Youshen Xiao , Fei Gao , Yuyao Zhang , Jingyi Yu , Xiran Cai

Ultrasound reflection tomography is widely used to image large complex specimens that are only accessible from a single side, such as well systems and nuclear power plant containment walls. Typical methods for inverting the measurement rely…

Image and Video Processing · Electrical Eng. & Systems 2018-10-01 Hani Almansouri , S. V. Venkatakrishnan , Gregery T. Buzzard , Charles A. Bouman , Hector Santos-Villalobos

Spectral domain optical coherence tomography (OCT) offers high resolution multidimensional imaging, but generally suffers from defocussing, intensity falloff and shot noise, causing artifacts and image degradation along the imaging depth.…

Image and Video Processing · Electrical Eng. & Systems 2021-08-04 Jonathan H. Mason , Yvonne Reinwald , Ying Yang , Sarah Waters , Alicia El Haj , Pierre O. Bagnaninchi

A method for photoacoustic tomography is presented that uses circular integrals of the acoustic wave for the reconstruction of a three-dimensional image. Image reconstruction is a two-step process: In the first step data from a stack of…

Numerical Analysis · Mathematics 2009-12-06 G. Zangerl , O. Scherzer , M. Haltmeier

In this article, we are concerned with a nonlinear inverse problem with a forward operator involving an unknown function. The problem arises in diverse applications and is challenging in the presence of an unknown function, which makes it…

Numerical Analysis · Mathematics 2023-02-07 Gyeongha Hwang , Gihyeon Jeon , Sunghwan Moon

In this article, we consider the reconstruction of $\rho(t)$ in the (time-fractional) diffusion equation $(\partial_t^\alpha-\triangle)u(x,t)=\rho(t)g(x)$ ($0<\alpha \le 1$) by the observation at a single point $x_0$. We are mainly…

Analysis of PDEs · Mathematics 2017-08-02 Yikan Liu , Zhidong Zhang

We establish a direct link between the time-reversal technique and the so-called adjoint method for imaging. Using this relationship, we derive new solution strategies for an inverse problem which arises in telecommunication. These…

Optimization and Control · Mathematics 2007-05-23 Oliver Dorn

Recovering images distorted by atmospheric turbulence is a challenging inverse problem due to the stochastic nature of turbulence. Although numerous turbulence mitigation (TM) algorithms have been proposed, their efficiency and…

Image and Video Processing · Electrical Eng. & Systems 2024-04-09 Xingguang Zhang , Nicholas Chimitt , Yiheng Chi , Zhiyuan Mao , Stanley H. Chan

The problem of recovering coefficients in a diffusion equation is one of the basic inverse problems. Perhaps the most important term is the one that couples the length and time scales and is often referred to as {\it the\/} diffusion…

Analysis of PDEs · Mathematics 2021-01-19 Barbara Kaltenbacher , William Rundell

In this paper, we consider the inverse boundary problems of recovering the time-dependent nonlinearity and damping term for a semilinear wave equation on a Riemannian manifold. The Carleman estimate and the construction of Gaussian beams…

Analysis of PDEs · Mathematics 2022-12-08 Song-Ren Fu
‹ Prev 1 4 5 6 7 8 10 Next ›